Epicycloidal gearing



F. F. DORSEY.

EPICYCLOIDAL (BEARING.

APPLICATION FILED NOV. 29, 1920.

Patented Nov. 1-41, 1922.

Fig, S: j 1' I l 2 In] 1 1| W L Nova 114, i922.

I wntrnn sraras PATENT crates.

panama r. nonsnr', or noonn's r na, WEWIYORK, assreitoa ro non'rn Ens'r nrinc'rnre COMPANY, or nocnnsrnn, new roan, a conroaa'rron or ainwroiair. H

- Y nrrovorornar. ennniive.

Application filed November 29, 1920. serial No. M75162.

I i To all whom-it may concern:

Be it known that I, FARNUM'JF. Donsrir,

a citizen of the United States, residin at Rochester, in the county-ofMonroe andv ta-te ofNew York, have invented certain new and useful Improvements inEpicycloidal Gearing; and I do hereby declarethe. following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to which it appertains-to'make and I y 1 'ripl ier esofthe gears'lt) and 11,

use the same. r

This invention relates repicyoloidfll'. gearing of the type in which a.ffplan'etail,

pinion or gear is supported by'fla rota 1 5 spider or carrier, While in engagement-wi two or more ternal form.

One object of the invention is I D same" planes, the parallelism of all axes is a gearing in which the structure, while tin "assured'j' and rigidly maintained, and the usually compact, provides ample bearin {3 surfaces for the several parts. Another o 5 ject of the invention is to pro duceflajgear;

. ing which may be readily assembled and disassembled, and which is of simple 2 form;- and construction, with a minimum numbeipretained a ainstaxial displacement in one *direction" ythe'i iember 13, and in the of parts. I a: To the foregoing ends it is pro osed to rovide the several elements of t e gearing withv bearing-surfaces adapted to coopso erate with the toothed surfaces ofv the gears and pinions, thereby dispensing with the usual journals and studs and securing the several advantages above set forth, fun a manner which will be apparent from the,

description of the preferred embodiment of the invention.

In the accompanying drawings Fig. 1 is a side-elevation of ar gearing embodying thepresent invention, and Fig. 2 is a horizontal to sectional view, on the line 2-2 in Fi 1. Fig. 3 is a side-elevation of a modified form 'of the invention, andFig. 4 is a vertical sectional View on the line H in Fig. 3. Fig. 5 is a detail-view showing the arrange ea merit of the gear-teeth in Figs. 1 and 2.

In Figs. 1 and 2 the invention is illustrated as embodied in a gearingof thetype in which the planetary pinionsrevolve while in engagement with two gears differing to slightly in number of teeth. Here the gears, 10 and 11, are located side-by side, and the gear 11 is keyed to a central'shaft 12. The

, gear 10 is keyed to a member 13 mounted loosely on the shaft. If one gear is held stationary the other will be rotated, and the formation? 'of' these parts.

gears of eitherexterrial Orin; p

* -'.',w1th, 1-t je QtOOiJhGClsurfaces. All working tuatedjby a rotary carrier 17. The noveltyof the invention resides particularly in the V r A p The carrier is boredftog beari-direotly on the toothed pea1-s'o-bored to provide two recesses which receive andconform closely to the pinions 16. h- ,m-anner the carrier and the pinh ef of" liar 'eiarea". and are axially coextensive parts and bearings are thus brought into the structure ifs rendered more compact than is possiblewith any other known structure-providing the same strength and the same extent of bearing-surfaces.

The planetary pinions and the carrier are other directionlby a plate 18 which may be loose on the shaft 12. The carrier is shown as provided with peripheral teeth 19 through which it may be rotated, as by the worm 20 shown in the drawings. This arrangement is particularly convenient where the gearing is used to actuate an odometer or counting mechanism by power derived from a rapidly rotating shaft, such as that of a tachometer.

In an epicycloidal gearing of the type in question it is customary to provide the two gears which are to be relatively rotated with numbers of teeth differing by one, or by a very small number. While this slight difference involves a slight difference in i -provided with bearings which are and it is pitch-diameter, the two gears may still co- I operate satisfactorily with a single'p'lanetary so that the depth of engagement need not 'vention it is desirable, though not necessary,

to give the carrier a bearing engagement with the peripheries of both gears. In order that this may be done without the necessity of boring the carrier to two different diameters, the arrangement of, the teeth on the gears is slightly modified.

' be'exact. In the gearing of the present in- The teeth-are also of the same form and thickness, but are spaced differently. Fig. 5

is a detail-view, on a greatly enlarged scale,

showin a few teeth on adj acentparts of the gears. Here the teeth 21 of the gear 10 are normal inbothform a-nd spacing, but the teeth 22 on the gear 11, while similar to the teeth 21, are spaced' farther apart, so that the gear 11 has at least two less teeth than thegear 10. While it is not possible, with this arrangement, to secure theoretically correct actionof the teetluit has beenfound that if the gears be cut with ample back-lash they will work satisfactorily formany purposes. V

Figs. -3and 4 show the application of the invention to a gearing of the-type in which the planetary pinion meshes with two gears in the same plane. Here the inner gear 23 is keyed to the shaft 24, while the outer geaiy 25 has internal teeth engaged'by the pinion 26. .The rotary carrier 27 has a cylindrical inner bearing-surface which turns on the gear 23, as in the construction previously described, and it has also a cylindrical outer surface on which, as a bearing, the gear 25 turns. The, carrier is also provided with a cylindrical recess serving asa bearing for the pinion 26. a I a Thexc'arrier 27 is provided with a hollow extension/28 by which it may be connected with any mechanism to turn or be turned by the gearing. The several rotary meme bers are retained against relative axial displacement by a flange 29 on the carrien'and a plate 30 mounted loosely on the shaft 24. The. gear: 25 is provided with external teeth, throughwhich it may drive or be driven by means such as a pinion 31.

While the drawings show. only two forms,

of gearing be apparent that it is applicable to many other types and varieties of epicycloidal gearing, within the scope of the following claims.

The invention claimed is:

1. Epic-ycloidal gearing comprising: a central gear with'an external toothed surface; a planetary pinion meshing with the gear; and a carrier surrounding said gear and having a concentric bearing-surface closely embracing the toothed surface of the gear and an eccentric bearing-surface'closely embracing the toothed surface of the pinion.

2. Epicycloidal gearing of the type comprising two coaxial gears arranged side-byside and having different numbers'of teeth,

, a carrier, and aplanetary pinion revoluble around the axis of said gears and meshing with both of them; said gearing character-' ized by the factthat said gears areof equal outside diameter but differenttooth-spacing and that the carrier has a cylindrical bearing-surface closely conforming to the outer surfaces of both gears, whereby the gears serve as an axial support for the carrier.

3. Epic-ycloidal gearing comprising: two coaxial gears arranged side-by-sideand havin r su frounding, said gears and having a cylin-' drical bearing-surface conformingto the outer surfaces of the gears, whereby the gears serve as an axialsupport for the carrier; a planetary pinion meshing with the two gears, substantially coextensive, longitudinally, with the carrier, the carrier being provided withja recess closely embracing the pinion to end thereof; and two'parallel end-plates independent of, but closely embracing the different numbers of teeth; acarrier embodying the 'invention,it will i and constituting a bearing from end carrier and retaining the carrier and the pinion against axial movement. I

FARNUM F, DOR SEY. 

